Studies on the immunity to intracellular infections, attributed to the effects of antibody and committed lymphocytes, have focused on macrophages in the past. This is a proposal to study this process in non-lymphoid cells of solid tissues, i.e., fibroblasts, kidney cells, epithelial cells, brain cells, etc. The protective effects of antibody, lymphoid cells and of soluble mediators on "somatic" cells will be studied and compared with the previously investigated effects on macrophages. Mice and hamsters, infected with Toxoplasma, Besnoitia, Histoplasma, murine cytomegalovirus and Listeria monocytogenes, are to be studied. However, the aim is to extend our understanding of intracellular infection towards an understanding of immunity in the body as a whole.